Non-planar drawings with large crossing angles
In evidenza

Crossings are considered one of the major factors that reduce the readability of the drawing of a graph. This is not only suggested by intuition but also confirmed by cognitive experiments showing that human performances degrade in the presence of edge crossings. For this reasons the study of planar drawings is a classical subject of investigation in the Graph Drawing field. Unfortunately, the graphs arising from real-world applications are often non-planar and crossings are therefore unavoidable.

On the other hand, recent cognitive experiments have shown that the human understanding of a graph drawing is not inhibited if edge crossings form large angles. These experiments suggest a new and fascinating research scenario in which the goal is to compute non-planar drawings where the smallest angle formed by two crossing edges is maximized. Based on these new ideas, Didimo, Eades and Liotta (WADS 2009, TCS 2011) introduced and studied RAC (Right Angle Crossing) drawings, i.e., drawings of graphs where edges cross forming right angles. After their definition, many papers have been published about RAC drawings, both from the combinatorial and the algorithmic point of view. Relaxations and generalizations of RAC drawings have also been introduced and studied.